Application of twin screw extruders for reactive processing

Reactive extrusion has grown in a few years from a specialized technique for creating experimental materials to the preferred production technique for manufacture of standard polymer systems (ex. polyurethanes) and modification of these systems (ex. grafting). The complexity of the extruder system design has also grown tremendously. The ability of reactive extrusion to produce a myriad of products in a single piece of capital equipment makes it attractive to R&D, manufacturing and financial groups.     

Computation of Multivariate Barrier Crossing Probability and its Applications in Credit Risk Models

Abstract

In this paper we consider computational methods of finding exit probabilities for a class of multivariate diffusion processes. Although there is an abundance of results for one-dimensional diffusion processes, for multivariate processes one has to rely on approximations or simulation methods. We adopt a Large Deviations approach to approximate barrier crossing probabilities of a multivariate Brownian Bridge. We use this approach in conjunction with simulation methods to develop an efficient method of obtaining barrier crossing probabilities of a multivariate Brownian motion. Using numerical examples, we demonstrate that our method works better than other existing methods. We mainly focus on a three-dimensional process, but our framework can be extended to higher dimensions. We present two applications of the proposed method in credit risk modeling. First, we show that we can efficiently estimate the default probabilities of several correlated credit risky entities. Second, we use this method to efficiently price a credit default swap (CDS) with several correlated reference entities. In a conventional approach one normally adopts an arbitrary copula to capture dependency among counterparties. The method we propose allows us to incorporate the instantaneous variance-covariance structure of the underlying process into the CDS prices.     

The sources of momentum in international government bond returns

This study aims to offer a new explanation for the momentum effect in international government bonds. Using cross-sectional and time-series tests, we examine a sample of bonds from 22 countries for the years 1980 through 2018. We document significant momentum profits that are not attributable to bond-specific risk factors, such as volatility or credit risk. The global bond momentum is driven by the returns on underlying foreign exchange rates. Controlling for currency movements fully explains the abnormal returns on momentum strategies in international government bonds. The results are robust to many considerations including alternative sorting periods, portfolio construction methods, as well as subperiod and subsample analysis.     

Where are the big bills? Escaping the endogenizer’s dilemma

The continual expansion of rational choice theory to a greater range of social phenomena—from markets to politics and institutions—is a testament to its success. Each further application, however, simultaneously forecloses a potential source of inefficiency in economic systems. Abdicating efficiency considerations impairs economics’ explanatory power as much as its normative relevance. In this paper I explore the interconnected roles of subjectivism and knowledge problems in accounting for inefficiency. I conclude that the knowledge-generating properties of institutions allow for efficiency comparisons, but only in the embrace of a thoroughgoing subjectivism.     

Economic growth under political accountability

We examine the impact of political and criminal accountability on economic growth. Governments seek to maximize their own consumption by extracting rents that are costly to growth. When citizens are able to depose politicians through elections, governments are tightly controlled. The rents politicians are able to extract increase in the length of their term. The effect of the threshold of criminal responsibility on the ability of voters to control politicians is non-monotonic. When tenure in power does not depend on economic performance, rent extraction is limited only by the effectiveness of oversight mechanisms but does not depend on time horizons of the rulers. Accumulation constraint binds only rulers who are neither politically nor criminally accountable.     

The impact of the institution of patent protection and enforcement on entry mode strategy: A panel data investigation of U.S. firms

The Trade-Related Aspects of Intellectual Property Rights (TRIPS) agreement has engendered a harmonisation of patent laws across countries but the extent of enforcement of these laws continues to vary. This study investigates the degree to which de jure book law protection of patents and de facto enforcement of these laws influences the propensity of firms to exploit their patented technology in foreign markets with company-owned operations or unrelated concerns using licensing agreements. Analyzing data on royalty and fee receipts of U.S. parent companies from affiliates and non-affiliated parties abroad from 1998 to 2007, and using separate measures for de jure and de facto patent protection and enforcement, we find that strengthening de jure protection induces greater affiliate licensing while strengthening de facto enforcement induces non-affiliate licensing. We conclude by observing that greater account should be taken of de facto enforcement measures when investigating the role of institutions on the international activities of firms.     

Creative mass. Consumption,creativity and innovation on Bangkok's fashion markets

The becoming productive of consumer culture has been an important theme for social research. Within neoliberal discourse, the link between consumer culture and new forms of immaterial production has been conceptualized as “creativity.” This paper uses the experience of Bangkok's fashion markets to begin to articulate an alternative understanding of the relation between consumer culture and immaterial production, a different kind of “creativity.” We suggest that Bangkok's fashion markets manifest a kind of creativity where innovation is highly socialized, as opposed to being oriented around the notion of individual genius and individual intellectual property; where participation is popular as opposed to elite-based and where the ambiguous relation between creation and commercial success that is intrinsic to Western notions of creativity is replaced by an embrace of markets and commerce as vehicles for self-expression. Bangkok's fashion markets represent an example of a market-based commons centered innovation economy.     

PRICING OF HIGH‐DIMENSIONAL AMERICAN OPTIONS BY NEURAL NETWORKS

Pricing of American options in discrete time is considered, where the option is allowed to be based on several underlyings. It is assumed that the price processes of the underlyings are given Markov processes. We use the Monte Carlo approach to generate artificial sample paths of these price processes, and then we use the least squares neural networks regression estimates to estimate from this data the so‐called continuation values, which are defined as mean values of the American options for given values of the underlyings at time t subject to the constraint that the options are not exercised at time t. Results concerning consistency and rate of convergence of the estimates are presented, and the pricing of American options is illustrated by simulated data.     

Reconciling microeconomic and macroeconomic estimates of price stickiness

This paper attempts to reconcile the high estimates of price stickiness from macroeconomic estimates of a New-Keynesian Phillips curve (NKPC) with the lower values obtained from surveys of firms’ pricing behaviour. This microeconomic evidence also suggests that the frequency with which firms adjust their prices varies across sectors. Building on the insights of Carvalho (2006), we present Monte Carlo evidence that suggests that in the presence of this heterogeneity estimates of the NKPC obtained using conventional methods, such as GMM, are likely to considerably overstate the degree of aggregate price stickiness. Furthermore, if roundabout production is a characteristic of the economy the NKPC will falsely suggest that a sizeable fraction of prices are indexed to past inflation. These problems arise because of a type of misspecification and a lack of suitable instruments.     

Return performance volatility and adaptation in an automated technical analysis approach to portfolio management

This paper discusses the design of a quantitative computational intelligence portfolio management system and evaluates the advantages of some adaptive mechanisms to enable the system to adjust its management approach as market conditions change. A detailed analysis of the performance of the system outside is also provided. It is found that an adaptive methodology where trading rules are able to adjust to market conditions performs better, having greater excess returns and lower volatility than a fixed rule approach. We consider several performance metrics, including portfolio alpha and information content. Copyright © 2009 John Wiley & Sons, Ltd.